Summary A Piper PA31-350 (registration C-FTIW, serial number 31-7752123), operated by Aropro, was on a visual flight rules (VFR) flight from Sept-les, Quebec, to Wabush, Newfoundland and Labrador. The pilot, who was the sole occupant, took off around 0630 eastern daylight time. Shortly before 0700, the aircraft turned off its route and proceeded to Grand lac Germain to fly over the cottage of friends. Around 0700, the aircraft overflew the southeast bay of Grand lac Germain. The pilot then overflew a second time. The aircraft proceeded northeast and disappeared behind the trees. A few seconds later, the twin-engine aircraft crashed on the frozen surface of the lake. The pilot was fatally injured; the aircraft was destroyed by impact forces. Ce rapport est galement disponible en franais. Other Factual Information History of the Flight About a week before the accident, the pilot planned to fly over the cottage of friends on Grand lac Germain, Quebec, if he had an opportunity. At approximately 2200 eastern daylight time1 the night before the accident, the company advised the pilot that he was required to do a medical evacuation (MEDEVAC) flight that was scheduled for the next morning. The aircraft was to fly to Wabush, Newfoundland and Labrador, and bring an ambulatory patient and a passenger back to Sept-les, Quebec. The pilot arrived at the company office at Sept-les Airport around 0500 to do the external inspection of the aircraft and prepare for the flight. At 0601, he filed a flight plan according to visual flight rules, which indicated that the pilot planned to take off at 0630for a direct flight to Wabush at an altitude of 5500feet above sea level(ASL). At 0630, the aircraft took off as planned, with the pilot as sole occupant, and set a direct heading for the destination. The winds were calm, the skies were clear, visibility was 30miles and the outside temperature was -13C. At 0635, the pilot reported five miles north of the airport at 2200feet climbing to 5500feet. That was the last message received from the pilot. Radar data indicate that, at 0637, the aircraft was on a heading for Wabush in level flight at 3500feetASL. At 0647, the aircraft disappeared from the radar screen. Around 0700, the aircraft arrived at Grand lac Germain, which is about 60miles north of Sept-les, 107miles south of Wabush and some 9miles to the west of the planned route. The aircraft flew over the area twice. The aircraft was not observed the first time it overflew the area. The second time it overflew the area, it flew a northeast heading and followed the downward slope of the terrain on the south side of the bay, passing about 500 feet to the east of the cottage. When it was over the lake, the aircraft arrested its descent at a height of approximately 100to 300feet. The aircraft's speed could not be determined. The landing gear was up and no anomalies were observed. The engine noise seemed constant and normal. Over the north shore of the bay, the aircraft initiated a gentle climb followed by a steep bank, then disappeared behind the trees. The aircraft roughly followed the west shore of the lake as it moved farther away from the cottage. The noise of an impact was heard a few seconds later. A few minutes after that, the aircraft was found broken up on the frozen surface of the lake. Pilot The pilot started flying PA31s for Aropro in March2006. He held a valid commercial pilot licence issued in June994 and a Group1 instrument rating. Examination of the pilot's logbook, Transport Canada records and the company records revealed that the pilot had about 790flying hours on PA31s. His total flying hours were approximately 5475, including 90hours in the last 30days before the accident. The pilot was considered by his peers and the instructor pilots as a competent and professional pilot. On the day of the accident, the pilot was based at Sept-les. His last previous flight was on 30March2007. The day before the accident, the pilot got up around 0700; he spent the day doing family activities and went to bed around2230. On the day of the accident, he got up around 0430 and left the house to go to the company office. According to the company operations manual, pilots are required to inform the operations manager of the number of hours they fly. The operations manager must ensure that the pilots' hours meet the regulatory requirements for flight time and flight duty time prescribed in Section700.15 of the Canadian Aviation Regulations (CARs). Since Transport Canada had issued an operating specification to the company to extend the flight time limitations, the company was required to ensure that pilots did not exceed the times specified in Section720.15. At the time of the accident, the last update on the form used to record the pilot's flight time, flight duty time, and rest periods was made on 23February2007. To determine the pilot's flight time from 23February2007 to the day of the accident, the logbooks for the aircraft operated by the company were used. The pilot's calculated flight time indicated that he did not exceed the limitations prescribed in Section720.15 of the CARs. Based on the information gathered, there is no evidence that fatigue was a factor in the accident. Test results for the presence of common drugs were negative. The autopsy report indicates that the pilot died as a result of the accident. Aircraft The Piper PA31-350 is a low-wing, twin-engine aircraft that can carry two pilots and up to eight passengers, depending on configuration. The aircraft was certified, equipped, and maintained in accordance with existing regulations and approved procedures. Its last inspection was on 29March2007. The number2 cylinder of the left engine was replaced. At the time of the accident, the aircraft had no outstanding maintenance items. No deficiencies had been reported or entered in the aircraft logbook. The pilot who flew the aircraft the day before the accident reported no particular problems. The aircraft was equipped for instrument flight. It was fitted with an autopilot and a radar altimeter. The aircraft was not equipped with a flight data recorder (FDR) or cockpit voice recorder (CVR), nor were they required under existing regulations. The aircraft had been modified to increase the maximum allowable take-off weight from 7000to 7368pounds. The Super Chieftain modification from Boundary Layer Research Inc. (Supplementary Type Certificate [STC] SA00192SE) consisted of four engine nacelle strakes and 88vortex generators affixed to the wings and vertical tail. The vortex generators improve the stall characteristics and lower the stall speed by about 8knots by controlling boundary layer airflow. Stall The stall speed of the aircraft at its estimated weight at the time of the accident- 5800pounds- was 67knots with the wings level, flaps retracted and no applied power. The aircraft weight and load factor have an effect on stall speed. For example, in a turn, the load factor increases according to the angle of bank. Consequently, the greater the bank angle, the higher the speed at which the aircraft will stall (see Table1). Also, to maintain constant altitude in a turn without applying more power, some speed must be sacrificed. In a climbing turn, the outer (high) wing will be the first to stall and sink. The manufacturer and owner of the STCstate that the maximum loss of altitude when recovering from a stall is 500feet. Table 1. Stall speed with vortex generators and no power The symptoms of an impending stall include sluggish control surfaces (loss of effectiveness), airframe vibration, and activation of the stall warning system. Pilots must decrease the angle of attack and minimize the loss of altitude. To do so, they must apply full throttle and take an attitude close to cruising attitude. The aircraft's stall warning system consists of a lift transducer vane and a backing plate located on the right-wing leading edge. The vane is able to move up or down within a range of motion afforded by a gap in the backing plate in which it is mounted. Aerodynamic pressure on the lift transducer vane varies with the wing's angle of attack. When an angle of attack approaches that of an imminent stall, the vane changes position, and the sensor unit produces a signal that activates the stall warning horn in the cockpit, 4to 10knots before the stall. The walk-around checklist in the aircraft operating manual does not require that the stall warning system be checked for serviceability. The investigation revealed that the company pilots did not routinely check the system for serviceability. Company The company's operations are governed by Section703, Air Taxi Operations, and Section 704, Commuter Operations, of the CARs. The Aropro head office is in Qubec, Quebec, and it has auxiliary bases in Saint-Hubert and Sept-les. C-FTIW operated out of Sept-les. At the time of the occurrence, Aropro was operating a fleet of about 14 aircraft (Cessna 310 and 337, Piper Navajo, Beech King Air90 and100, and Embraer110). Aropro uses a pilot self-dispatch system. The pilot is fully responsible for preparing, planning and conducting the flight. He is also required to ensure that the flight is conducted in accordance with existing regulations and company procedures as published in the company operations manual. The company operations manual states that the pilot-in-command is responsible for monitoring the flight. The pilot-in-command is required to advise the person who authorized the flight or the qualified person on duty as soon as the itinerary or schedule is changed. The company has no particular requirements for MEDEVAC flights. Aropro did, however, use two pilots on MEDEVAC flights to facilitate patient boarding. Since there were no requirements to that effect, the presence of a co-pilot was left to the discretion of the pilot-in-command. The pilot was not able to make contact with another pilot before the flight for undetermined reasons; he decided to carry out the flight on his own. The pilot did not advise the company that he was going to complete the flight alone. When the aircraft was reported missing, the company advised the search and rescue centre that there were two pilots on board, since the aircraft was on a MEDEVAC flight. Accident Site The accident occurred on the frozen surface of the southeast bay of Grand lac Germain, at an elevation of 1780feet ASL. The aircraft struck the frozen surface of the lake 525feet east of the shoreline it was flying over and 275feet west of an island in the middle of the bay. The aircraft crashed approximately 2300feet northeast of the cottage and 1600feet after disappearing behind the trees. The aircraft broke through the top layer of ice, which was about two inches thick, then bounced off the second layer of ice. The impact produced a crater 30feet in circumference. Photo1.Aerial view of accident site The aircraft heading was 117M at the time of impact, which is 14 off the breakup trajectory. Photogrammetric analysis of the crater established that the aircraft struck the ice surface in a low right bank attitude with the nose slightly up. The slope of the flight path was approximately 18 downward. From the point of impact, the sun was at 115M and at 8 above the horizon. Wreckage The wreckage was examined to the extent possible. The aircraft broke into several pieces. The breakup trajectory was on a heading of 103M. The wreckage trail was approximately 250feet long and an average 40feet wide. The wing tips were found 50feet from the point of impact. The cabin roof was completely torn off. The cockpit and cabin were so damaged by impact forces that the occupant space was almost completely reduced. The accident was not survivable. The landing gear was up. Both engines separated from the aircraft under impact forces. Examination of the propellers established that, at the time of impact, they were at low pitch, which is consistent with cruise engine power. It was also determined that the two engines were at the same throttle setting. The engine rpm could not be determined. The two flap actuators were examined at the TSB Engineering Laboratory, and it was confirmed that they were in the retracted position at the time of impact. Readings were taken from the needle marks imprinted on the faces of the two airspeed indicators and one vertical speed indicator at the time of impact. The marks indicated that both airspeed indicators read 67knots and that the vertical speed indicator showed a rate of descent of 1900feet per minute. There was a significant dent in the right wing tip that was approximately five inches in diameter. No debris was found in this imprint or inside the wing that could be used to identify the object that was struck. The imprint of a blade was observed in the dent. The investigation did not determine whether the right wing struck a tree in flight or another object during the breakup sequence. Bird strike was ruled out because no bird remains were found. Due to the extent of impact damage, it was not possible to establish flight control continuity at the time of the accident. However, none of the components examined revealed any deficiencies that would have impeded control of the aircraft. No signs of in-flight fire were found. The fuel system console was retrieved and sent to the TSB Engineering Laboratory for analysis. The fuel tank selector for the left engine was found in the closed position; examination revealed that it moved freely. Normally, the lever must be lifted in order to move it. The incandescent filament in the indicator light was found intact, indicating that it was not illuminated at the time of impact and that fuel was being supplied to both engines. VFR Flight Obstacle Clearance Requirements The operation of Aropro's PA31 was subject to PartVII, Subpart3, of the CARs. Section703.27 of the CARs requires that companies governed by Subpart703 that conduct daytime VFR flights not operate the aircraft at less than 300feet above ground level (AGL) or at a horizontal distance of less than 300feet from any obstacle. At the time of the accident, the Aropro company operations manual did not make provision for the restrictions on daytime VFR flights prescribed in Section703.27 of the CARs. Illusion Created by Low-Altitude Flight When flying at normal altitude, an aircraft seems to be moving slowly relative to the ground. The proximity of the ground tends to capture the pilot's attention and create the illusion of higher speed relative to the ground, to the point where the pilot may be tempted to reduce speed.